NEW ZEALAND

GOVERNMENT GAZETTE,

PROVINCE OF CANTERBURY.

Published by Authority.

All Public Notifications which appear in this Gazette, with any Official Signature,
are to be considered as Official Communications made to those Persons to whom they may
relate, and are to be obeyed accordingly.

By His Honor’s command,
H. G. GOULAND,
Provincial Secretary.

Vol. I.] TUESDAY, DECEMBER 19, 1854. [No. XXVII.]

Provincial Secretary’s Office,
Christchurch, December 17, 1854.

HIS HONOR THE SUPERINTENDENT directs the following Report,
received from Captain Drury, of H.M.S. Pandora, respecting the navigation of the
Sumner Bar, to be published for general information.

By order of His Honor the Superintendent,
H. G. GOULAND,
Provincial Secretary.

H. M. S. Pandora, Port Victoria,
18th December, 1854.

Sir,

Having at your request examined the entrance of the Sumner, with a view to determine the possibility of rendering its navigation easier by removing obstacles, or otherwise improving it, I herewith transmit a report, and shall have much pleasure in forwarding you a tracing of the survey in a few days to be attached to this report.

We find the mouth of the Sumner to be situated two and a half miles N.W. of Godley Head, at the southern extreme of a long sandy beach; that the stream in meeting a projection of rocks on its south shore, bends rather suddenly from an eastern to a northern course; from this bend the bar is one-quarter of a mile and one-sixth of a mile from the outer rock. (These rocks are above water.) It is 400 feet in width, with a depth at low water springs of not less than 5 feet in the channel; the soundings on either side of the bar decrease towards it gradually.

The narrowest part of the channel within the bar is 150 feet; it is between the elbow and the rocks: but on passing this, where a vessel would turn, there is a space of 400 feet with not less than 9 feet at low water, and in the channel to the Shag Rock 10 to 11 feet.

The deepest water is found on the channel side of the rocks, 24 feet at low water.

The highest water on the bar would be 12 feet in springs, 9 to 10 feet at neaps, the rise and fall being from 7 feet in springs to 5 feet at neaps. The bar is composed of fine sand, the strength of current (I should think) never exceeds 5 to 6 knots.

With due deference to any opinions suggested for the improvement of the entrance, I have after three days’ investigation come to the conclusion, that any money expended in improving or altering the course of the outlet, would be more likely to be detrimental to navigation than otherwise.

Of the number of similar bar harbours on the east coast of Great Britain, attempts at considerable expense have not only been rendered fruitless, but in most cases, engineering has been detrimental to the harbour, and the formations of angular piers, sea walls, &c., have eventually done injury to the cause they were intended to remove, by accumulating deposit.

Although in some few instances, by obtaining a considerable scouring power by sluices, and sea walls diverging towards the embouchure, the effect has assisted in deepening the channel to some small extent; yet such expense and its problematical result, would not justify even consideration in this case.

However, since some suggestions have been put forward with regard to supposed improvements, and without arrogating any knowledge on engineering subjects, I may simply state what occurs to me would be the practicable results of interfering with the channel as it exists.